Special Issue
  • Effect of Particle Size on the Thermal and Mechanical Properties of cBN-Reinforced Aluminum Matrix Composites

  • Dawoon Jung*, **, Minsu Kim*, Taeho Lee*, **, Hyeonjae Park*, **, Junghwan Kim*, Sang-Bok Lee*, Sang-Kwan Lee*, Yangdo Kim**, Seungchan Cho*†

  • * Composites Research Division, Korea Institute of Materials Science, Changwon, Korea
    ** School of Materials Science and Engineering, Pusan National University, Busan, Korea

  • cBN 입자 크기에 따른 알루미늄 복합재료의 열적 및 기계적 특성 연구

  • 정다운*, ** · 김민수* · 이태호*, ** · 박현재*, ** · 김정환* · 이상복* · 이상관* · 김양도** · 조승찬*†

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In this study, aluminum matrix composites uniformly reinforced with high-volume-fraction cubic boron nitride (cBN) particles were fabricated using a liquid pressing process, and their thermal and mechanical properties were analyzed based on particle size. The cBN/Al composites exhibited overall excellent thermal and mechanical properties, but showed distinct trends depending on particle size. Due to the constraint effect of cBN reinforcements and their excellent interfacial properties, the 15 μm cBN/Al1050 composite displayed the highest bending strength (527 MPa) and the lowest coefficient of thermal expansion (7.96 × 10-6 K-1). Conversely, due to the thermal resistance at the metal/ceramic interface, the thermal conductivity of the composite was maximized at 324.11 W/m·K for the 300 μm cBN/Al1050 composite, which had the smallest interfacial area. Therefore, the high-volume-fraction cBN/Al composites fabricated via the liquid pressing process demonstrated superior thermal and mechanical properties, and it was confirmed that these properties can be effectively tailored by controlling the size of the reinforcement particles.


본 연구에서는 액상가압공정을 이용하여 cubic boron nitride(cBN) 입자가 균일하게 분산된 고체적률 알루미늄(Al) 복합재료를 제조하였고 입자 크기에 따른 열적, 기계적 특성을 분석하였다. 제조된 cBN/Al 복합재료의 경우 전반적으로 우수한 열적, 기계적 특성을 나타내었으나 입자 크기에 따라 상이한 경향을 나타내었다. cBN 강화재의 구속효과 및 우수한 계면 특성으로 인하여 cBN 입자 크기가 작은 15 μm cBN/Al1050 복합재료의 경우 가장 높은 굽힘강도(527 MPa) 및 가장 낮은 열팽창계수(7.96 × 10-6 K-1)를 나타냈다. 반면, 금속/세라믹 계면 열저항으로 인해 복합재료의 열전도도는 계면의 면적이 가장 적은 300 μm cBN/Al1050 복합재료에서 324.11 W/mK로 최대값을 나타내었다. 따라서, 액상가압공정으로 제조된 고체적률 cBN/Al 복합재료의 경우 우수한 열적, 기계적 특성을 나타내었으며, 강화재의 크기를 조절함으로써 복합재료의 열적 및 기계적 특성을 적절히 제어할 수 있음을 확인하였다.


Keywords: 알루미늄 복합재료(Aluminum matrix composites), 액상가압공정(Liquid pressing process), 열팽창계수(Coefficient of thermal expansion), 열전도도(Thermal conductivity)

This Article

Correspondence to

  • Seungchan Cho

  • Composites Research Division, Korea Institute of Materials Science, Changwon, Korea

  • E-mail: sccho@kims.re.kr